The present invention is related to methods for making a pair of electrodes that may be used in a diode device. The term diode device encompasses, for example, thermionic converters and generators, photoelectric converters and generators, and vacuum diode heat pumps. It is also related to thermotunnel converters.
WO99/13562 and U.S. Pat. No. 6,417,060 disclose methods for making pairs of electrodes whose surfaces replicate each other. The methods involve fabricating a composite by providing a first electrode with a substantially flat surface and placing a sacrificial layer over it. A second material, which will form the second electrode is placed over the sacrificial layer. The composite is then ‘split’ into two matching electrodes by removing the sacrificial layer by etching, by cooling the sandwich with liquid nitrogen, or by heating to evaporate the sacrificial layer.
The present invention offers a novel means for providing similarly paired electrodes in which a low work function material is introduced onto one or both of the electrode surfaces.